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oned and others where blunt axes were brought to be resharpened。
olorgesailie was； in short； a kind of factory； one that stayed in business for a million years。
various replications have shown that the axes were tricky and labor…intensive objects tomake鈥攅ven with practice； an axe would take hours to fashion鈥攁nd yet； curiously； they werenot particularly good for cutting or chopping or scraping or any of the other tasks to whichthey were presumably put。 so we are left with the position that for a million years鈥攆ar； farlonger than our own species has even been in existence； much less engaged in continuous cooperative efforts鈥攅arly people came in considerable numbers to this particular site to makeextravagantly large numbers of tools that appear to have been rather curiously pointless。
and who were these people？ we have no idea actually。 we assume they were homoerectus because there are no other known candidates； which means that at their peak鈥攖heirpeak 鈥攖he olorgesailie workers would have had the brains of a modern infant。 but there is nophysical evidence on which to base a conclusion。 despite over sixty years of searching； nohuman bone has ever been found in or around the vicinity of olorgesailie。 however muchtime they spent there shaping rocks； it appears they went elsewhere to die。
鈥渋t鈥檚 all a mystery；鈥潯illani ngalli told me； beaming happily。
the olorgesailie people disappeared from the scene about 200；000 years ago when the lakedried up and the rift valley started to bee the hot and challenging place it is today。 butby this time their days as a species were already numbered。 the world was about to get itsfirst real master race； homo sapiens 。 things would never be the same again。
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Goodbye
in the early 1680s； at just about the time that edmond halley and his friends christopherwren and robert hooke were settling down in a london coffeehouse and embarking on thecasual wager that would result eventually in isaac newton鈥檚 principia ； henry cavendish鈥檚weighing of the earth； and many of the other inspired and mendable undertakings thathave occupied us for much of the past four hundred pages； a rather less desirable milestonewas being passed on the island of mauritius； far out in the indian ocean some eight hundredmiles off the east coast of madagascar。
there； some forgotten sailor or sailor鈥檚 pet was harrying to death the last of the dodos； thefamously flightless bird whose dim but trusting nature and lack of leggy zip made it a ratherirresistible target for bored young tars on shore leave。 millions of years of peaceful isolationhad not prepared it for the erratic and deeply unnerving behavior of human beings。
we don鈥檛 know precisely the circumstances； or even year； attending the last moments of thelast dodo； so we don鈥檛 know which arrived first； a world that contained a principia or one thathad no dodos； but we do know that they happened at more or less the same time。 you wouldbe hard pressed； i would submit； to find a better pairing of occurrences to illustrate the divineand felonious nature of the human being鈥攁 species of organism that is capable of unpickingthe deepest secrets of the heavens while at the same time pounding into extinction； for nopurpose at all； a creature that never did us any harm and wasn鈥檛 even remotely capable ofunderstanding what we were doing to it as we did it。 indeed； dodos were so spectacularlyshort on insight； it is reported； that if you wished to find all the dodos in a vicinity you hadonly to catch one and set it to squawking； and all the others would waddle along to see whatwas up。
the indignities to the poor dodo didn鈥檛 end quite there。 in 1755； some seventy years afterthe last dodo鈥檚 death； the director of the ashmolean museum in oxford decided that theinstitution鈥檚 stuffed dodo was being unpleasantly musty and ordered it tossed on abonfire。 this was a surprising decision as it was by this time the only dodo in existence；stuffed or otherwise。 a passing employee； aghast； tried to rescue the bird but could save onlyits head and part of one limb。
as a result of this and other departures from mon sense； we are not now entirely surewhat a living dodo was like。 we possess much less information than most people suppose鈥攁handful of crude descriptions by 鈥渦nscientific voyagers； three or four oil paintings； and a fewscattered osseous fragments；鈥潯n the somewhat aggrieved words of the nineteenth…centurynaturalist h。 e。 strickland。 as strickland wistfully observed； we have more physical evidenceof some ancient sea monsters and lumbering saurapods than we do of a bird that lived intomodern times and required nothing of us to survive except our absence。
so what is known of the dodo is this： it lived on mauritius； was plump but not tasty； andwas the biggest…ever member of the pigeon family； though by quite what margin is unknownas its weight was never accurately recorded。 extrapolations from strickland鈥檚 鈥渙sseous fragments鈥潯nd the ashmolean鈥檚 modest remains show that it was a little over two and a halffeet tall and about the same distance from beak tip to backside。 being flightless； it nested onthe ground； leaving its eggs and chicks tragically easy prey for pigs； dogs； and monkeysbrought to the island by outsiders。 it was probably extinct by 1683 and was most certainlygone by 1693。 beyond that we know almost nothing except of course that we will not see itslike again。 we know nothing of its reproductive habits and diet； where it ranged； what soundsit made in tranquility or alarm。 we don鈥檛 possess a single dodo egg。
from beginning to end our acquaintance with animate dodos lasted just seventy years。 thatis a breathtakingly scanty period鈥攖hough it must be said that by this point in our history wedid have thousands of years of practice behind us in the matter of irreversible eliminations。
nobody knows quite how destructive human beings are； but it is a fact that over the last fiftythousand years or so wherever we have gone animals have tended to vanish； in oftenastonishingly large numbers。
in america； thirty genera of large animals鈥攕ome very large indeed鈥攄isappearedpractically at a stroke after the arrival of modern humans on the continent between ten andtwenty thousand years ago。 altogether north and south america between them lost aboutthree quarters of their big animals once man the hunter arrived with his flint…headed spearsand keen organizational capabilities。 europe and asia； where the animals had had longer toevolve a useful wariness of humans； lost between a third and a half of their big creatures。
australia； for exactly the opposite reasons； lost no less than 95 percent。
because the early hunter populations were paratively small and the animal populationstruly monumental鈥攁s many as ten million mammoth carcasses are thought to lie frozen in thetundra of northern siberia alone鈥攕ome authorities think there must be other explanations；possibly involving climate change or some kind of pandemic。 as ross macphee of theamerican museum of natural history put it： 鈥渢here鈥檚 no material benefit to huntingdangerous animals more often than you need to鈥攖here are only so many mammoth steaksyou can eat。鈥潯thers believe it may have been almost criminally easy to catch and clobberprey。 鈥渋n australia and the americas；鈥潯ays tim flannery； 鈥渢he animals probably didn鈥檛 knowenough to run away。鈥�
some of the creatures that were lost were singularly spectacular and would take a littlemanaging if they were still around。 imagine ground sloths that could look into an upstairswindow； tortoises nearly the size of a small fiat； monitor lizards twenty feet long baskingbeside desert highways in western australia。 alas； they are gone and we live on a muchdiminished planet。 today； across the whole world； only four types of really hefty （a metric tonor more） land animals survive： elephants； rhinos； hippos； and giraffes。 not for tens of millionsof years has life on earth been so diminutive and tame。
the question that arises is whether the disappearances of the stone age and disappearancesof more recent times are in effect part of a single extinction event鈥攚het